1. Field of the Invention
The present invention relates to a flow sensing device, or an electronics apparatus installed in an engine room of an internal combustion engine.
2. Description of the Related Art
As set forth in JP-A 8-338279, the electronics apparatus installed in an engine room has hitherto been configured so that the case thereof is formed of members such as a metal base, a resin housing, and a resin cover, and so that electronics circuitry is included inside the case.
In order to dissipate the self-heating of the electronics circuitry, the metal base is connected to the electronic circuit board with an adhesive therebetween, and it is made of a material high in heat dissipation efficiency and relatively inexpensive, such as aluminum. The adhesive connecting the metal base and the resin housing employs a material that is soft, extendable, weather-resistant, and chemical-resistant, such as silicone adhesive, in order to withstand thermal deformation due to the difference in the coefficient of thermal expansion between the metal base and the resin housing.
To electrically connect the electronics circuitry in its inside to the outside, the resin housing involves metal terminals by integral molding, and the connection between the resin housing and the electronics circuitry is established by aluminum wire bonding or welding.
The electrical circuitry portion is formed by printing conductors, resistors, and a thick insulating film paste, and baking them. In order to protecting conductors, the electrical circuitry may be formed by finally printing and baking a coating glass. However, in this case, land portions for soldering components and portions of the conductors themselves to which a measuring probe to be applied for characteristics adjustment, are left exposed.